塔里木盆地寒武系碳酸盐岩层序地层特征

摘要

运用碳酸盐岩层序地层学理论,通过野外露头观察、钻井资料分析及地震剖面综合解释技术,开展塔里木盆地下古生界碳酸盐岩层序地层研究,识别层序边界,建立地层格架.对塔里木盆地寒武系碳酸盐岩识别出的8个层序特征进行刻画,除层序SQ1为基准面上升半旋回型层序外,其他层序均为基准面下降半旋回型层序,其中层序SQ5,SQ6,SQ7,SQ8为重点勘探层序.在轮南地区,层序SQ6,SQ7,SQ8为今后构造-岩性复合圈闭重点勘探层序.建立了塔里木盆地寒武系碳酸盐岩层序发育模式,指出了有利于碳酸盐岩储层发育的层序样式,为寻找地层-岩性圈闭发育有利部位提供了依据.%Sequence stratigraphic theories of carbonate are employed in a sequence stratigraphic study on the Lower Paleozoic carbonates in Tarim Basin through outcrop observation, drilling data analysis as well as integrated seismic interpretations. Together with the study, the sequence boundaries are identified and stratigraphic framework is established. As a result, eight sequences identified in the Cambrian carbonates are described. Except for sequence 1 (SQ 1 ) as a ascending base level semi-cycle sequence, the other sequences are all falling base level semi-cycle sequences. Sequences 5, 6, 7 and 8 are considered key hydrocarbon exploration targets.In Lunnan area, exploration activities shall be focused on sequences 6, 7 and 8 for complex structural-lithologic traps. A model for the Cambrian carbonate sequences in the Tarim Basin is developed and provides helpful aid to searching for places with favorable conditions for the formation of stratigraphic lithologic traps.